According to OWC's specifications, the housing supports "port multiplier" - which is necessary because eSata is otherwise only a point-to-point connection (as in a PC with Sata). However, your eSata port/eSata card must also support this, which is not always the case. Check your port :)

OWC Mercury Elite Pro Dual (MED3ER0GB) -------------------------------------- - Interfaces: USB 3.1 Gen 1 (5 Gb/s) + eSATA 6 Gb/s - Max. Speed: approx. 407 MB/s (read/write) - RAID modes: Hardware RAID 0, 1, SPAN, Independent - Integrated USB hub: No - Cooling: Standard fan - Special feature: eSATA connection OWC Mercury Elite Pro Dual (MEDCH7T00) -------------------------------------- - Interfaces: USB 3.2 Gen 2 (10 Gb/s) - Max. Speed: up to approx. 1250 MB/s - RAID modes: Hardware RAID 0, 1, SPAN, JBOD - Integrated USB hub: Yes (1× USB-C + 2× USB-A) - Cooling: 60 mm fan, Kensington slot - Special feature: Premium version with USB hub Main differences -------------------------------------- - MEDCH7T00 is twice as fast (USB 3.2 Gen 2 vs. USB 3.1 Gen 1) - MEDCH7T00 has an integrated USB hub (1× USB-C + 2× USB-A) - MED3ER0GB has eSATA, MEDCH7T00 does not - MEDCH7T00 offers JBOD, MED3ER0GB only Independent

As the article OWC Mercury Elite Pro Dual is currently no longer available, it is currently not possible for us to verify compatibility with your WD Red hard drives directly with the supplier. However, OWC is generally known for its good compatibility with common NAS and RAID hard drives such as the WD Red series - especially in RAID 0 mode.

The Mercury Elite Pro Dual (3.5", 2.5") from Other World Computing is compatible with Apple devices. It has ports such as eSATA, USB 3.2 and Thunderbolt 2 that work with Macs and other Apple products that support these interfaces.

If you assume that there is only a USB B 2.0 connector. However, a B has also existed as a 3.0 version for some time. https://de.wikipedia.org/wiki/Universal_Serial_Bus#Spezifikationen